Cracking catalysts of the prior art which include faujasite zeolites of the X and Y type have been formed by spray drying a slurry of the zeolite and a matrix. The matrix may include alumina or silica-alumina gels or other organic oxide gels and clays or mixtures thereof.
Cracking catalysts containing the faujasite type zeolite known as zeolite Y, (see Breck U.S. Pat. No. 3,130,007 patent) and containing also alumina and clay and ammonium polysilicate (See Lim et al, U.S. Pat. No. 4,086,187) when produced by spray drying of a water slurry of the above components in the form of microspheres will have a suitable attrition resistance provided that the alumina is in the form of a hydrate having suitable rheological properties as set forth in co-pending application, Ser. No. 003,407, filed Jan. 15, 1979 now U.S. Pat. No. 4,086,187, incorporated herein by this reference, of which this application is a continuation-in-part.
The pseudoboehmites are classified in said application as type A and type B according to a test procedure described in said application. Said application is incorporated in this application by this reference. See also Lim et al, U.S. Pat. No. 4,086,187.
The problem of obtaining such catalyst which are of suitable attrition properties are discussed in said copending applications, and in said patent. The prior art cited and referred to in said application and Patent are also included in the statement of the Background.